1. Field of the Invention
This invention relates to apparatus and methods for straightening carpet, and more particularly, to an apparatus for straightening carpet after it has left the mill and is otherwise ready for installation.
2. Brief Description of the Prior Art
Carpet is produced at mills in large rolls as is well known. The length or longitudinal direction of the carpet in these rolls can be several times the width or transverse direction of the roll. As the carpet is produced at the mill, the woven or tufted material is notoriously not straight. That is, the weave can vary considerably along the length of the carpet. This is not a significant problem for plain carpet, but it can be very noticeable on carpet which has a pattern in it, particularly when that pattern has a transversely extending feature to it. For example, a carpet which nominally has a plurality of transversely extending parallel straight lines may actually look like it has wavy lines in it.
Historically, these problems with lack of straightness in carpet patterns have had to be fixed by the carpet installer. That is, when laying the carpet, the installer has had to pull longitudinally on the carpet at various places along its length to bring the pattern back into its proper relationship. Using the parallel line example again, the installer has to pull to stretch the carpet until the transverse lines actually appear straight. There are a number of tools designed to engage the surface of the carpet and allow for such stretching. Many of these devices are manually operated, although some have mechanical actuation such as by a hydraulic cylinder. All have disadvantages in that they must be moved to the installation site and relocated on the surface of the carpet at each point in the installation process at which the installer decides is necessary. This greatly increases installation time and cost for laying patterned carpet and can require considerable physical exertion by the installer.
Another problem is that, even with these straightening techniques, mill tolerances are sometimes so great that installers cannot get the carpet straight enough manually and noticeable variations remain.
There is a need, therefore, for an apparatus for straightening carpet at the installation site, or elsewhere, which reduces the time required in prior art installations and is not so physically demanding on installation personnel. The present invention solves this problem by providing an apparatus comprising a heating section wherein the backing on the carpet is softened enough that the carpet can be straightened even when the pattern varies so much that normal manual straightening techniques on carpet at ambient temperatures are not sufficient. As the carpet exits the heating section, it enters a hydraulically controlled straightening section which allows forces in a longitudinal direction to be applied at various locations across the width of the carpet. This powered stretching allows the operator to straighten the heated carpet regardless of the large tolerances in the pattern. After straightening, the apparatus has a cooling section in which the carpet is allowed to cool after being stretched so that the pattern remains straight. The carpet then exits the apparatus with the pattern straightened. The roll of carpet may then be installed much more quickly because the installer does not have to do as much to the carpet as it is laid on the floor.